Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS6235948 B1
Publication typeGrant
Application numberUS 09/374,942
Publication dateMay 22, 2001
Filing dateAug 16, 1999
Priority dateAug 18, 1998
Fee statusLapsed
Also published asCA2339185A1, CN1190399C, CN1313843A, DE69914773D1, DE69914773T2, EP1105363A1, EP1105363B1, WO2000010953A1
Publication number09374942, 374942, US 6235948 B1, US 6235948B1, US-B1-6235948, US6235948 B1, US6235948B1
InventorsHari Babu Sunkara, John Umile II Robert
Original AssigneeE. I. Du Pont De Nemours And Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Process for the purification of 1,3-propanediol
US 6235948 B1
Abstract
Disclosed is a process for the removal of impurities, especially color forming impurities, from 1,3-propanediol.
Images(5)
Previous page
Next page
Claims(26)
What is claimed is:
1. A process for the purification of 1,3-propanediol comprising the steps of
a) contacting 1,3-propanediol with an acid catalyst at a temperature above that required for impurities to react and below that required for extensive ether formation, said temperature being above about 100° C.; and
b) isolating purified 1,3-propanediol from impurities, reacted impurities and the acid catalyst.
2. The process of claim 1 wherein the purified 1,3-propanediol is isolated by 1) separating the acid catalyst and 2) distilling 1,3-propanediol from the impurities and reacted impurities.
3. The process of claim 1 wherein the temperature in step a is less than 160° C.
4. The process of claim 3 wherein the temperature in step a is between 130 and 150° C.
5. The process of claim 1 wherein the acid catalyst is insoluble in 1,3-propanediol acid.
6. The process of claim 5 wherein the acid catalyst is a solid.
7. The process of claim 6 wherein the solid acid catalyst is selected from the group consisting of perfluorinated ion-exchange polymers (PFIEP) containing pendant sulfonic acid groups or pendant carboxylic acid groups, acid zeolites, and acid clays.
8. The process of claim 7 wherein the solid acid catalyst is selected from the group consisting of perfluorinated ion-exchange polymers containing pendant sulfonic acid groups, silica or alumina supported perfluorinated ion-exchange polymers containing pendant sulfonic acid groups and porous nanocomposites of perfluorinated ion-exchange polymers containing pendant sulfonic acid groups and silica.
9. The process of claim 1, wherein the temperature is at least 130° C.
10. A process for the purification of 1,3-propanediol consisting essentially of the sequential steps of:
a) treating 1,3-propanediol with solid acid catalyst at a temperature of above about 100 to 160° C.;
b) removing the solid acid catalyst by filtering or decanting; and
c) isolating purified 1,3-propanediol from impurities by distillation.
11. The process of claim 10 wherein step a) is carried out at 130-160° C.
12. The process of claim 10 wherein step a) is carried out at 130-150° C.
13. The process of claim 10 wherein the 1,3-propanediol is cooled to room temperature prior to step b).
14. The process of claim 10 wherein the distillation is carried out under reduced pressure.
15. The process of claim 10 wherein the 1,3-propanediol contains colored precursors as an impurity and the colored precursors are transformed to separable compounds.
16. The process of claim 10 which is carried out in a continuous process.
17. The process of claim 10 which is carried out in a batch process.
18. A process for the purification of 1,3-propanediol comprising:
a) treating a mixture consisting essentially of 1,3-propanediol and acid catalyst at a temperature of about 100-160° C.; and
b) isolating purified 1,3-propanediol by distillation.
19. The process of claim 18 wherein step a) is carried out at 130-160° C.
20. The process of claim 18 wherein step a) is carried out at 130-150° C.
21. The process of claim 18 wherein the acid catalyst is a solid acid catalyst.
22. The process of claim 20 wherein the acid catalyst is a solid acid catalyst.
23. The process of claim 18 wherein treatment is carried out for 0.1-3 hours.
24. The process of claim 1, further comprising polymerizing the purified 1,3-propanediol in the presence of acid catalyst to obtain polyether polyol.
25. The process of claim 1, further comprising preparing a polyester from the purified 1,3-propanediol.
26. The process of claim 1, comprising first preparing 1,3-propanediol and then the steps a) and b).
Description

This application claims the benefit of Provisional No. 60/096,939 filed Aug. 18, 1998.

FIELD OF THE INVENTION

This invention concerns a process for the removal of impurities, especially color forming impurities, from 1,3-propanediol.

TECHNICAL BACKGROUND OF THE INVENTION

1,3-Propanediol is a precursor for polyether glycols, polyester bomopolymers and copolymers, and thermoplastic elastomers. The quality of these products is in general dependent on the quality of the raw materials. For some applications, such as fibers, color quality is a major concern. It is known that products derived from 1,3-propanediol have suffered from discoloration. Commercially available samples of 1,3-propanediol starting materials have resulted in brown colored polyether glycols. Disclosed attempts to remove color from the products made from available 1,3-propanediol have been laborious and expensive. Even after extensive purification processes, many products retain a yellow color.

U.S. Pat. No. 2,520,733 discloses a process for the purification of polyols prepared from 1,3-propanediol in the presence of acid catalyst (2.5 to 6% by weight) and at a temperature from about 175° C. to 200° C. This purification process involves percolation of the polymer through Fuller's earth followed by hydrogenation. Even after this extensive purification process, the final product remains light yellow in color.

U.S. Pat. No. 3,326,985 discloses a procedure for the preparation of poly(1,3-propanediol) of molecular weights in the range of 1200-1400 possessing improved color by vacuum stripping, under nitrogen, poly(1,3-propanediol) of lower molecular weight.

U.S. Pat. No. 5,659,089 discloses a process for the preparation of poly(2-methyl-1,3-propanediol) by the etherification of 2-methyl-1,3-propanediol. No diol purification process is given. Any available grade of diol can be used in the etherification process.

U.S. Pat. No. 5,527,973 discloses a process for providing a purified 1,3 propanediol which can be used as a starting material for low color polyester. That process has several disadvantages including the use of large equipment and the need for dilution with large quantities of water which is difficult to remove from the product.

The process of the present invention alleviates the problem of discolored polymer production in a relatively simple and economical process. The process of the present invention involves purification of, and removal of color precursors from the starting reactant 1,3-propanediol rather than treating the resulting products. The purified diol from this process is useful for preparing a variety of polymers that include polyether glycols, polyesters and thermoplastic elastomers having excellent color characteristics.

SUMMARY OF THE INVENTION

Disclosed is a process for the purification of 1,3-propanediol comprising the steps of

a) contacting 1,3-propanediol with an acid catalyst at a temperature above that required for impurities to react and below that required for extensive ether formation; and

b) separating purified 1,3-propanediol from impurities, reacted impurities and the acid catalyst.

DETAILED DESCRIPTION OF THE INVENTION

In the preparation of low molecular weight polyether glycols via the dehydration of 1,3-propanediol, polyol quality is an important item. For some applications, such as the production of fibers, color is a major concern. In the past, attempts to prepare polytrimethylene glycols having good color properties have been unsuccessful. This invention discloses a process for the preparation of purified 1,3-propanediol so that products made from it, polyols, polyester homopolymers and copolymers, and thermoplastic elastomers, have excellent color characteristics.

Color-free, i.e., chromophore-free, polyether glycols have been prepared from 1,3-propanediol that has been purified of chromophore precursors by a two step process. The first step in the treatment of the diol to free it of color formers (referred to herein as “color precursors”) involves the contacting of the 1,3-propanediol with an acid catalyst at elevated temperatures. While not wishing to be bound by any mechanism, applicant believes this step converts color precursors and other impurities to colored and uncolored derivatives that, due to their changed chemical nature, are easily separable from 1,3-propanediol. The second step of the purification process involves the separation of the desirable, purified 1,3-propanediol from the formed colored and uncolored derivatives, from the acid catalyst employed to effect the conversion and, potentially, from residual impurities.

An acid catalyst is employed in the treatment process. This acid catalyst promotes the conversion of chromophore precursors to chromophores. The type of acid, (homogeneous or heterogeneous), nature (strong or weak) and the amount of acid catalyst can be varied widely. Although soluble acid catalysts, including inorganic acids and organic sulfonic acids, can be used, heterogeneous acid catalysts are usually preferred because they can be removed more easily and can easily be recycled. Soluble catalysts, if used, can be removed by extraction or neutralization. Solid heterogeneous acid catalysts can be removed by filtration. Fixed heterogeneous catalyst may also be used, i.e., in a continuous process, provided that contact time is sufficient. Suitable heterogeneous catalysts are perfluorinated ion-exchange polymers (PFIEP) containing pendant sulfonic acid groups or pendant carboxylic acid groups, including NafionŽ catalyst, obtainable from the DuPont Company, which is an example of perfluorinated ion-exchange polymers containing pendant sulfonic acid groups, silica or alumina supported NafionŽ catalyst, NafionŽ Superacid catalyst, a porous nanocomposite of NafionŽ resin and silica, acid zeolites, or acid clays.

The amount of acid catalyst used herein is not critical, as long as sufficient catalyst is present. Small amounts of catalyst may necessitate extended treatment times. In the case of commercial NafionŽ NR50 catalyst, 1% by weight of catalyst versus the weight of 1,3-propanediol was convenient in a batch treatment process. The amount of catalyst employed, in batch treatment processes, will generally be within the range of about 0.1 to 5 wt % based on the amount of 1,3-propanediol used.

The temperature for the acid treatment step is selected such that the reaction that converts chromophore precursors readily occurs, but the dehydration reaction of 1,3-propanediol is essentially avoided. The process of the invention is carried out by heating the 1,3-propanediol and the acid catalyst at a temperature within the range of about 100-160° C. for 0.1-3 hours under nitrogen atmosphere. At temperature greater than 170° C., the acid can function as a dehydrating catalyst that could lead to the formation of polyether glycols from the 1,3-propanediol. Preferably, the reaction temperature is maintained within the range of 130° C.-150° C. so that chromophore precursor reaction occurs but essentially no dimers or trimers of 1,3-propanediol are formed.

The acid treatment is most conveniently carried out at atmospheric or above atmospheric pressures.

In a preferred mode of operation, after the color precursors are transformed, the mixture is cooled to room temperature, and the solid catalyst is removed either by filtration or by decantation. The filtered mixture is then distilled under reduced pressure, and the 1,3-propanediol is collected. The colored impurities and other impurities are left in the distillation flask. The absence of acid catalyst during the vacuum distillation process limits the occurrence of 1,3-propanediol dehydration reactions.

The purification of 1,3-propanediol, as described above, can be carried out in either a batch process or a continuous process. The treatment maybe carried out in an agitated system or, if the acid catalyst is in solid form or adhered/attached to a solid support, the treatment may be carried out by passing the diol over or through a bed of the solid acid catalyst.

The process can be conducted as a stand alone process, carried out on available 1,3-propanediol. Alternatively, it may be integrated within a 1,3-propanediol manufacturing process—carried out as one of the steps of a 1,3-propanediol manufacturing process. The 1,3-propanediol may be prepared by a variety of manufacturing processes, including the hydration of acrolein followed by hydrogenation of the resulting hydroxypropanal, or the hydroformylation of ethylene oxide followed by reduction of the resulting hydroxypropanal. The purification process may by integrated within either of these or other manufacturing processes.

The purified 1,3-propanediol is isolated by means known in the art, most preferably by vacuum distilling the diol away from the converted color precursors and colored and uncolored derivatives.

In subsequent processing, the purified diol may be polymerized in the presence of either soluble or insoluble acid catalyst to obtain colorless polyether polyol of low molecular weights. In alternate end uses, the purified diol may be used to prepare polyesters, for example poly(1,3-propylene terephthalate) by methods known in the art.

Depending upon the intensity of the color of the samples to be measured, two different color scales are used. For light colored products, Platinum-Cobalt (APHA) Standard and for dark colored products Gardner Standard are used.

EXAMPLES Example 1 Purification Process of 1,3-propanediol Using NafionŽ Acid Catalyst

A 5 L-three necked flask equipped with a distillation column, mechanical stirrer and nitrogen inlet was charged with 1,3-propanediol (3714.2 g) (commercial grade, Degussa) and NafionŽ NR50 catalyst (37.147 g)(DuPont). The mixture was stirred mechanically and heated to 130° C. under nitrogen atmosphere. At this temperature, the liquid turned yellow. The liquid then turned brown as it was heated to 150° C. The temperature was kept constant at 150° C. for about 2 hours and then allowed to cool to room temperature. No distillate was collected at the receiver flask indicating that essentially no dehydration reaction occurred under these conditions. The solid acid catalyst was removed by decanting the colored solution. Then, the diol was isolated from the colored impurities by distilling at 100° C. under reduced pressure. The APHA color values as measured on a HunterLab ColorQuest (Hunter Associates Laboratory, Inc., Reston, Va.) for the purified diol and the original diol are 3 and 7 respectively, indicating an improvement in color characteristics of the purified diol.

Heating the thus purified 1,3-propanediol to reflux, under nitrogen, for 3 hours caused the APHA color to increase from 3 to 20. Similar treatment of the starting 1,3-propanediol gave a colored product having APHA color of 60 (i.e., a change from 7 to 60 APHA color). Example 2, below, and comparative example 1, wherein these two samples of 1,3-propanediol are converted to poly(1,3-propanediol) further illustrate the efficacy of the process of the present invention in removing color forming impurities.

Example 2 Synthesis of Poly(1,3-propanediol) from Purified 1,3-propanediol

To a 250 mL three-necked flask, 152.2 g (2.0 mol) of purified 1,3-propanediol, prepared as in Example 1, and 1.903 g (10 mmol) of p-toluenesulfonic acid (Aldrich Chemical Co, Milwaukee, Wis.) were added at room temperature. The mixture was stirred and heated to 180-200° C. under nitrogen atmosphere. The distillate (33.1 mL), mostly water was collected as the dehydration reaction progress. The reaction was stopped after 5.5 hours and the mixture was cooled to room temperature. Colorless poly(1,3-propanediol) was obtained from this process. The APHA color value for the polyol was measured and had a value of 48.

Comparative Example 1 Synthesis of Poly(1,3-propanediol) from Unpurified 1,3-propanediol

To 152.2 g (2.0 mol) of 1,3-propanediol (commercial grade, Degussa), 1.903 g (10 mmol) of p-toluenesulfonic acid was added. The mixture was stirred and heated under nitrogen atmosphere. As the temperature of the reaction mixture increased, the color formation was observed at the temperature of 130° C. and then the dehydration reaction occurred at 180-200° C. About 32.5 mL of distillate was collected during the dehydration reaction which continued for a time period of 5.5 hours. The color properties of the polyol was measured and had a APHA color value of >300, i.e., off the APHA color scale. The color was measured in Gardner units using a Hellige Daylite Comparator Illuminator (Hellige, Inc., Garden City, N.Y.) which gave a Gardner value of 4.

Example 3 A Larger Scale Diol Purification

The 1,3-propanediol purification process described in Example 1 was scaled up. A 30-gallon glass-lined clave was charged with polymer grade 1,3-propanediol (176 lb) and NafionŽ NR50 catalyst (1.76 lb). The mixture was stirred mechanically and heated to 150° C. under nitrogen atmosphere. The temperature was kept constant at 150° C. for about two hours and then allowed to cool to room temperature. After cooling, the clave was discharged through a filter to recover the solid acid catalyst. The discolored diol solution, that has an APHA color value greater than 300, was distilled in batches using a 22 L-three necked flask equipped with a distillation column, mechanical stirrer and nitrogen inlet at 120° C. under reduced pressure. After the distillation was complete the purified diol (144 lb), has an APHA color value of 3. Heating the thus purified 1,3-propanediol to reflux, under nitrogen for 3 hours caused the APHA color value to increase from 3 to 12. As described in Example 2, poly(1,3-propanediol) was made with the purified diol and the APHA color value of the polymer was 30.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2520733Aug 26, 1946Aug 29, 1950Shell DevPolymers of trimethylene glycol
US3326985Dec 29, 1964Jun 20, 1967Shell Oil CoPolytrimethylene glycol
US4937314Feb 28, 1989Jun 26, 1990E. I. Du Pont De Nemours And CompanyCopolyetherester elastomer with poly(1,3-propylene terephthalate) hard segment
US4970295Feb 27, 1989Nov 13, 1990Arco Chemical Technology, Inc.Preparation of oxetane polyether polyols using a bleaching earth catalyst
US5008473Sep 17, 1987Apr 16, 1991Ruhrchemie AktiengesellschaftProcess for purifying propanediol-1,3
US5128185Aug 29, 1991Jul 7, 1992E. I. Du Pont De Nemours And CompanyCopolyetherester elastomer with poly(1,3-propylenebibenzoate) hard segment
US5194159Dec 18, 1991Mar 16, 1993Union Carbide Chemicals & Plastics Technology CorporationTreatment of lower glycol-containing operative fluids
US5364987Jul 6, 1993Nov 15, 1994Degussa AktiengesellschaftProcess for the preparation of 1,3-propanediol
US5403912Nov 26, 1991Apr 4, 1995Commonwealth Scientific And Industrial Research OrganizationProcess for the production of poly(alkylene oxide)
US5527973Dec 16, 1994Jun 18, 1996Kelsey; Donald R.Purification of 1,3-propanediol
US5659089May 22, 1996Aug 19, 1997Arco Chemical Technology, L.P.Process for making poly(2-methyl-1,3-propanediol)
Non-Patent Citations
Reference
1M. J. Rhoad and P.J. flory, J. Am. Chem. Soc. 72, 2216 (1949).
2Nafion(R) SAC Superacid Catalyst Product Information (1999).
3Nafion(R) Superacid Resins NR-50 and NR-40 Product Information.
4NafionŽ SAC Superacid Catalyst Product Information (1999).
5NafionŽ Superacid Resins NR-50 and NR-40 Product Information.
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6562457Oct 31, 2001May 13, 2003E. I. Du Pont De Nemours And CompanyPolyether ester elastomer comprising polytrimethylene ether ester soft segment and tetramethylene ester hard segment
US6599625Oct 31, 2001Jul 29, 2003E. I. Du Pont De Nemours And CompanyPolyether ester elastomer comprising polytrimethylene ether ester soft segment and trimethylene ester hard segment
US6693222Apr 29, 2002Feb 17, 2004E. I. Du Pont De Nemours And CompanyProcess for splitting water-soluble ethers
US6720459Dec 15, 2000Apr 13, 2004E. I. Du Pont Nemours And CompanyContinuous process for the preparation of polytrimethylene ether glycol
US6852823Aug 9, 2002Feb 8, 2005E. I. Du Pont De Nemours And CompanyPolyurethane and polyurethane-urea elastomers from polytrimethylene ether glycol
US6969779Oct 1, 2003Nov 29, 2005Shell Oil CompanyMethod for removal of MW176 cyclic acetal formed during the production of 1,3-propanediol
US6972346Oct 1, 2003Dec 6, 2005Shell Oil CompanySolid acid catalyzed reactive stripping of impurities formed during the production of 1, 3-propanediol
US6977291Dec 15, 2000Dec 20, 2005E.I. Du Pont De Nemours And CompanyProduction of polytrimethylene ether glycol and copolymers thereof
US7009082Aug 5, 2003Mar 7, 2006E.I. Du Pont De Nemours And CompanyRemoval of color bodies from polytrimethylene ether glycol polymers
US7038092Aug 12, 2005May 2, 2006E. I. Du Pont De Nemours And CompanyPurification of chemical 1,3-propanediol
US7074968Jan 20, 2004Jul 11, 2006E. I. Du Pont De Nemours And CompanyContinuous process for the preparation of polytrimethylene ether glycol
US7074969Jun 18, 2004Jul 11, 2006E.I. Du Pont De Nemours And CompanyProcess for preparation of polytrimethylene ether glycols
US7084311Aug 5, 2003Aug 1, 2006E. I. Du Pont De Nemours And CompanyHydrogenation of chemically derived 1,3-propanediol
US7098368May 5, 2004Aug 29, 2006E. I. Du Pont De Nemours And CompanyHydrogenation of biochemical derived 1,3 -propanediol
US7147815Jun 26, 2003Dec 12, 2006E. I. Du Pont De Nemours And CompanyPoly(trimethylene terephthalate) bicomponent fiber process
US7157607Aug 16, 2005Jan 2, 2007E. I. Du Pont De Nemours And CompanyManufacture of polytrimethylene ether glycol
US7161045Aug 16, 2005Jan 9, 2007E. I. Du Pont De Nemours And CompanyProcess for manufacture of polytrimethylene ether glycol
US7164046Jan 20, 2006Jan 16, 2007E. I. Du Pont De Nemours And CompanyManufacture of polytrimethylene ether glycol
US7211699Aug 12, 2005May 1, 2007E. I. Du Pont De Nemours And CompanyPurification of biochemically derived 1,3-propanediol
US7244790May 2, 2005Jul 17, 2007E.I. Du Pont De Nemours And CompanyThermoplastic elastomer blend, method of manufacture and use thereof
US7294746Nov 10, 2005Nov 13, 2007E.I. Du Pont De Nemours And CompanyProcesses for removal of color bodies from polytrimethylene ether glycol polymers
US7323539Aug 12, 2004Jan 29, 2008E. I. Du Pont De Nemours And CompanyPolytrimethylene ether glycol and polytrimethylene ether ester with excellent quality
US7357985Sep 19, 2005Apr 15, 2008E.I. Du Pont De Nemours And CompanyHigh crimp bicomponent fibers
US7358211Nov 24, 2004Apr 15, 2008E.I. Du Pont De Nemours And CompanyCatalyst for the production of 1,3-propanediol by catalytic hydrogenation of 3-hydroxypropanal
US7388115Nov 15, 2006Jun 17, 2008E. I. Du Pont De Nemours And CompanyManufacture of polytrimethylene ether glycol
US7531593Oct 31, 2006May 12, 2009E.I. Du Pont De Nemours And CompanyThermoplastic elastomer blend composition
US7645853Jan 12, 2010E.I. Du Pont De Nemours And CompanyProcesses for producing random polytrimethylene ether ester
US7666501Nov 29, 2006Feb 23, 2010E. I. Du Pont De Nemours And CompanyPoly(trimethylene terephthalate)/poly(alpha-hydroxy acid) bi-constituent filaments
US7714174Mar 27, 2007May 11, 2010E. I. Du Pont De Nemours And CompanyLower-color polytrimethylene ether glycol using hydride compounds
US7745668Aug 3, 2007Jun 29, 2010E. I. Du Pont De Nemours And CompanyProcesses for reducing color in polytrimethylene ether glycol polymers
US7919017Nov 12, 2007Apr 5, 2011E. I. Du Pont De Nemours And CompanyElectrical insulation fluids for use in electrical apparatus
US8058326Feb 12, 2009Nov 15, 2011E. I. Du Pont De Nemours And CompanyFluorescent poly(alkylene terephthalate) compositions
US8066923Nov 29, 2011E.I. Du Pont De Nemours And CompanyPoly(trimethylene terephthalate)/poly(alpha-hydroxy acid) biconstituent filaments
US8226859Aug 20, 2010Jul 24, 2012E I Du Pont De Nemours And CompanyElectrical insulation fluids for use in electrical apparatus
US8247526Aug 21, 2012E I Du Pont De Nemours And CompanyProcess for the preparation of polyalkylene ether glycol
US8344098Jan 1, 2013E I Du Pont De Nemours And CompanyProcesses for producing polytrimethylene ether glycol and copolymers thereof
US8598391Sep 29, 2010Dec 3, 2013E I Du Pont De Nemours And CompanyPolytrimethylene ether glycol or copolymers thereof having improved color and processes for their preparation
US8703681Dec 21, 2010Apr 22, 2014E I Du Pont De Nemours And CompanyLubrication oil compositions
US8758660Feb 21, 2008Jun 24, 2014E I Du Pont De Nemours And CompanyProcess of making high crimp bicomponent fibers
US8759559Apr 18, 2012Jun 24, 2014E I Du Pont De Nemours And CompanyProcesses for preparing polytrimethylene ether glycol esters
US8759565Jun 23, 2010Jun 24, 2014E I Du Pont De Nemours And CompanyPolytrimethylene ether glycol esters
US20020007043 *Dec 15, 2000Jan 17, 2002Sunkara Hari B.Production of polytrimethylene ether glycol and copolymers thereof
US20040087818 *Oct 1, 2003May 6, 2004Brewer Stephen EdwardMethod for removal of MW176 cyclic acetal formed during the production of 1,3-propanediol
US20040087819 *Oct 1, 2003May 6, 2004Powell Joseph BrounSolid acid catalyzed reactive stripping of impurities formed during the production of 1, 3-propanediol
US20040152925 *Jan 20, 2004Aug 5, 2004E.I. Du Pont De Nemours And CompanyContinuous process for the preparation of polytrimethylene ether glycol
US20040222544 *Jun 26, 2003Nov 11, 2004Chang Jing C.Poly(trimethylene terephthalate) bicomponent fiber process
US20040225107 *Aug 5, 2003Nov 11, 2004Sunkara Hari BabuPolytrimethylene ether glycol with excellent quality from biochemically-derived 1,3-propanediol
US20040225161 *Aug 5, 2003Nov 11, 2004Sunkara Hari BabuHydrogenation of chemically derived 1,3-propanediol
US20040225162 *Aug 5, 2003Nov 11, 2004Sunkara Hari BabuRemoval of color bodies from polytrimethylene ether glycol polymers
US20040260125 *May 5, 2004Dec 23, 2004Mayis SeapanHydrogenation of biochemical derived 1,3 -propanediol
US20050020805 *Aug 12, 2004Jan 27, 2005Sunkara Hari BabuPolytrimethylene ether glycol and polytrimethylene ether ester with excellent quality
US20050272962 *Aug 12, 2005Dec 8, 2005Sunkara Hari BPurification of chemical 1,3-propanediol
US20050277792 *Aug 12, 2005Dec 15, 2005Mayis SeapanPurification of biochemically derived 1,3-propanediol
US20050283028 *Jun 18, 2004Dec 22, 2005Sunkara Hari BProcess for preparation of polytrimethylene ether glocols
US20060041039 *Oct 8, 2004Feb 23, 2006Gyorgyi FenyvesiFluorescent poly(alkylene terephthalate) compositions
US20060069290 *Nov 10, 2005Mar 30, 2006Sunkara Hari BProcesses for removal of color bodies from polytrimethylene ether glycol polymers
US20060111595 *Nov 24, 2004May 25, 2006Eng John HCatalyst for the production of 1,3-propanediol by catalytic hydrogenation of 3-hydroxypropanal
US20060161027 *Nov 8, 2005Jul 20, 2006Mitsubishi Chemical CorporationMethod of producing 1, 3-propanediol
US20060247378 *Aug 30, 2005Nov 2, 2006Sunkara Hari BThermoplastic elastomer blend, method of manufacture and use thereof
US20060247380 *May 2, 2005Nov 2, 2006Sunkara Hari BThermoplastic elastomer blend, method of manufacture and use thereof
US20070035057 *Oct 19, 2006Feb 15, 2007Chang Jing CPoly(trimethylene terephthalate) bicomponent fiber process
US20070065664 *Sep 19, 2005Mar 22, 2007Kurian Joseph VHigh crimp bicomponent fibers
US20070128436 *Nov 29, 2006Jun 7, 2007Kurian Joseph VPoly(trimethylene terephthalate)/poly(alpha-hydroxy acid) bi-constituent filaments
US20070128459 *Nov 29, 2006Jun 7, 2007Kurian Joseph VPoly(trimethylene terephthalate)/poly(alpha-hydroxy acid) films
US20070129503 *Nov 29, 2006Jun 7, 2007Kurian Joseph VPoly(trimethylene terephthalate)/poly(alpha-hydroxy acid) molded, shaped articles
US20070129524 *Dec 6, 2005Jun 7, 2007Sunkara Hari BThermoplastic polyurethanes comprising polytrimethylene ether soft segments
US20070173669 *Nov 15, 2006Jul 26, 2007Hari Babu SunkaraManufacture of polytrimethylene ether glycol
US20070203371 *Jan 18, 2007Aug 30, 2007Sunkara Hari BProcess for producing polytrimethylene ether glycol
US20070276164 *Aug 3, 2007Nov 29, 2007E. I. Dupont De Nemours And CompanyProcesses for Reducing Color in Polytrimethylene Ether Glycol Polymers
US20080039582 *Jul 24, 2007Feb 14, 2008Hari Babu SunkaraPolytrimethylene ether-based polyurethane ionomers
US20080103217 *Oct 31, 2006May 1, 2008Hari Babu SunkaraPolyether ester elastomer composition
US20080103243 *Oct 31, 2006May 1, 2008Hari Babu SunkaraThermoplastic elastomer blend composition
US20080108845 *Nov 7, 2006May 8, 2008Hari Babu SunkaraPolytrimethylene ether glycol esters
US20080135662 *Dec 6, 2006Jun 12, 2008Chang Jing CMelt-spun elastoester multifilament yarns
US20080143009 *Feb 21, 2008Jun 19, 2008E. I. Du Pont De Nemours And CompanyHigh crimp bicomponent fibers
US20080242830 *Mar 27, 2007Oct 2, 2008Yanhui NiuLower-color polytrimethylene ether glycol using hydride compounds
US20090054280 *Aug 21, 2008Feb 26, 2009E.I. Dupont De Nemours And CompanyLubrication oil compositions
US20090054282 *Aug 21, 2008Feb 26, 2009E.I. Dupont De Nemours And CompanyLubrication oil compositions
US20090054283 *Aug 21, 2008Feb 26, 2009E.I. Dupont De Nemours And CompanyLubrication oil compositions
US20090054284 *Aug 21, 2008Feb 26, 2009E. I. Dupont De Nemours And CompanyLubrication oil compositions
US20090121200 *Nov 12, 2007May 14, 2009Bates Lisa CElectrical Insulation Fluids for Use in Electrical Apparatus
US20090146106 *Feb 12, 2009Jun 11, 2009E. I. Du Pont De Nemours And CompanyFluorescent poly(alkylene terephthalate) compositions
US20100105841 *Jan 6, 2010Apr 29, 2010E. I. Du Pont De Nemours And CompanyPoly(trimethylene terephthalate)/poly(alpha-hydroxy acid) biconstituent filaments
US20100261932 *Jun 23, 2010Oct 14, 2010E.I. Du Pont De Nemours And CompanyPolytrimethylene ether glycol esters
US20100267994 *Oct 21, 2010E. I. Du Pont De Nemours And CompanyProcesses for preparing polytrimethylene glycol using ion exchange resins
US20100308283 *Dec 9, 2010E. I. Du Pont De Nemours And CompanyElectrical insulation fluids for use in electrical apparatus
US20110021697 *Jan 27, 2011E. I. Du Pont De Nemours And CompanyMethods for preparing polyether ester elastomer composition
US20110152498 *Dec 17, 2010Jun 23, 2011E. I. Du Pont De Nemours And CompanyProcesses for producing polytrimethylene ether glycol and copolymers thereof
US20110172360 *Jul 14, 2011E.I. Du Pont De Nemours And CompanyMethods for synthesizing polyether diols and polyester diols
CN102040475BOct 21, 2009Jul 24, 2013中国石油化工股份有限公司Method for purifying 1,3-propylene glycol
CN102388084A *Apr 15, 2010Mar 21, 2012纳幕尔杜邦公司Processes for preparing polytrimethylene glycol using ion exchange resins
DE112007002474T5Oct 31, 2007Sep 17, 2009E.I. Du Pont De Nemours And Co., WilmingtonPolyetherester-Elastomerzusammensetzung
DE112007002477T5Oct 31, 2007Sep 10, 2009E.I. Du Pont De Nemours And Company, WilmingtonThermoplastische Elastomergemisch-Zusammensetzung
EP1620380A2 *May 5, 2004Feb 1, 2006E.I. Dupont De Nemours And CompanyRemoval of color bodies from polytrimethylene ether glycol polymers
EP1620489A2 *May 5, 2004Feb 1, 2006E.I. Dupont De Nemours And CompanyPolytrimethylene ether glycol with excellent quality from biochemically-derived 1,3-propanediol
EP2270065A2Dec 16, 2005Jan 5, 2011E. I. du Pont de Nemours and CompanyPoly(trimethylene terephthalate) composition and shaped articles prepared therefrom
EP2390278A1May 5, 2004Nov 30, 2011E.I. Dupont De Nemours And CompanyRemoval of color bodies from polytrimethylene ether glycol polymers
EP2419473A2 *Apr 15, 2010Feb 22, 2012E. I. du Pont de Nemours and CompanyProcesses for preparing polytrimethylene glycol using ion exchange resins
WO2004101470A2May 5, 2004Nov 25, 2004E.I. Dupont De Nemours And CompanyRemoval of color bodies from polytrimethylene ether glycol polymers
WO2010121021A2 *Apr 15, 2010Oct 21, 2010E.I. Du Pont De Nemours And CompanyProcesses for preparing polytrimethylene glycol using ion exchange resins
WO2010121021A3 *Apr 15, 2010Jan 13, 2011E.I. Du Pont De Nemours And CompanyProcesses for preparing polytrimethylene glycol using ion exchange resins
Classifications
U.S. Classification568/868, 568/872
International ClassificationC07C31/20, C07C29/80, C07C29/88
Cooperative ClassificationC07C29/80, C07C29/88
European ClassificationC07C29/88, C07C29/80
Legal Events
DateCodeEventDescription
Oct 21, 1999ASAssignment
Owner name: E.I. DU PONT DE NEMOURS AND COMPANY, DELAWARE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SUNKARA, HARI BABU;UMILE, ROBERT JOHN II;REEL/FRAME:010320/0834
Effective date: 19990830
Oct 29, 2002CCCertificate of correction
Sep 22, 2004FPAYFee payment
Year of fee payment: 4
Oct 23, 2008FPAYFee payment
Year of fee payment: 8
Dec 31, 2012REMIMaintenance fee reminder mailed
May 22, 2013LAPSLapse for failure to pay maintenance fees
Jul 9, 2013FPExpired due to failure to pay maintenance fee
Effective date: 20130522